South Africa weren’t switched on at the start of the game and it showed after just nine minutes of Algeria pressure, as their dangerman Oussama Darfalou was gifted the easiest of opening goals.
A route-one clearance was made by Algeria, Abbubakker Mobara didn’t step up with the rest of the line and looked to have played Darfalou on, Jody February came off his line as Kwanda Mngonyama struggled to get back to the man he left free, and Darfalou just lobbed it over the goalkeeper.
A few minutes later February showed good reactions to produce a great diving save from Mohammed Benkhemassa, whose shot was heading into the top-left corner.
Then in the very next attack Gift Motupa missed a golden opportunity to equalise out of nothing. Following a neat flick from Riyaad Norodien on the touchline, Mobara ran free down the right, beat a defender in the box and put in a bobbling cross from the byline, but South Africa’s top scorer could not hit the target, unmarked, six yards out.
Algeria totally dominated the opening exchanges but South Africa gradually started to get their act together as the half went on, although they found the going tough against a very organised team.
Then three minutes before half-time Mngonyama went a small way to making up for his underwhleming performances in the tournament so far with a brilliant last-ditch block to prevent Algeria going 2-0 up just before half-time.
Owen da Gama’s side turned the screw towards the end of the half, with Norodien in particular looking lively, but they could not breach the Algerian defensive wall.
It was 1-0 to Algeria at half-time.
And it was 2-0 just five minutes after the restart. An Algeria corner was cleared only as far as Benkhemassa 25 yards out, and he rifled a powerful, swerving shot through a crowd of players and past February into the bottom-right corner.
Da Gama brough on speedster Phakamani Mahlambi for the hardworking and industrious Norodien in the 53rd minute, and Dumisani Zuma for Menzi Masuku in the 64th. Prior to that substitution Masuku's best contribution was a pass to Deolin Mekoa at the far post, but he could not connect with the ball and a good chance went abegging.
Mahlambi's impact was immediate, and his personal battle with defender Ayoub Abdellaoui was a feature of the second half, the Bidvest Wits defender clearly being man-marked and kept at bay effectively despite being South Africa's brightest player after entering the fray.
Rivaldo Coetzee had a free header in the closing stages but failed to hit the target and Mobara had a close-range header saved – their keeper's only real save of the game – and that was as good as it got despite a valiant effort from Da Gama's boys as they chased the game in the closing period.
Algeria will play Nigeria in the Final, and South Africa will need to beat host nation Senegal in the third-place play-off and avenge their opening-day defeat to qualify for the Olympics next year.
Algeria XI: Salhi, Keniche, Ferhani, Abdellaoui, Benguit, Draoui, Benkhemassa, Ferhat, Ben Taharm, Darfalou, Chita
South Africa XI: February, Mngonyama, Coetzee, Moerane, Mobara, Dolly (c), P Ntshangase, Masuku (Zuma 64'), Mekoa, Norodien (Mahlambi 53'), Motupa